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Passenger Side Eletric Window Not Working

clive2016

Member
Hi Guys

Can anyone shed some light, the front passenger electric window isn’t working correctly.
Operating the window from the driver’s side it moves up and down, no problem so the issue is not the motor.

However, using the passenger side switch the window will go down but not back up.

Looking at the female plug there appears to be 3 wires and using a multimeter one of them is ground, another wire I get a reading of 2.75volts and the 3rd wire I get no voltage or ground.

Does anyone know which wires I need to bridge to check for up and down operation, incidentally I’m talking about the female part of the plug.

If the window goes up and down by bridging the wires then I assume the fault must be in the male part ie the rocker switch itself.

Anyone have any ideas how to test it without me burning something out?


Thanks

Clive
 

rjenkinsgb

Well-Known Member
Most Helpful Member
Without knowing what vehicle you are referring to, it's impossible to say how it is wired.

However, from what you describe it's the passenger switch to about 90% certainty.
 

Diver300

Well-Known Member
Most Helpful Member
The switches will have contacts that close that close when the switch is operated in the up direction, and others that close when the switch is operated in the down direction. A bad connection on the up contacts will cause the symptoms you saw.

There are many ways that window switches in cars work. The ones that I've seen include:-
Direct switches where the motor current is carried by the switches.
Switches wired to a control module, with separate wires for up and down, and possibly separate wires for one-touch and normal.
Switch pack containing individual switches that sends signals to a control module using a serial link.
Switch pack using capacitive sensing of finger position, sending signals to the control module using a serial link.

Which vehicle and model year is it?
 

clive2016

Member
Hi fellas

Thanks for your prompt replies, the car is a VW Golf MK5 TDi Sport year 2006.

Iv'e included a wiring diagram if you can make sense of it, I'm not into them.Wiring.JPG
 

Diver300

Well-Known Member
Most Helpful Member
OK, so the way the switches work on that car isn't on my list.......

That is called a resistor ladder. The switch (88) signals to the control box (68) by selecting different resistors between connections T4am/4 and T4am/1

I don't know what the resistances will be, but it looks like it's a 5 position switch, which would be one-touch down, normal down, switch released, normal up, and one-touch up. I think that switch released gives no connection, and one of the others gives zero resistance. All the other will be different resistances, probably in the range 1 to 10 kOhms.

If the passenger side switch works in one direction, then the wiring must be OK and it's probably the switch. You could try cleaning the contacts up, but new switches (probably copies, not originals) are <£10 on Ebay
 
If you had access to a scan tool, you could probably retrieve fault codes and monitor the switches as you press and release them. In this case though, Diver300 probably has it nailed down. You could do a resistance test on it between terminals 1 and 4 and see if they work or not. That would verify your diagnostics.
 
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Diver300

Well-Known Member
Most Helpful Member
You might not get a fault code if the switch is not making contact.

The might be a routine to test the switch, where the diagnostics would show if the switch was being pressed, which would allow the technician to see if that responded when the switch is pressed.
 
You are correct. You may not get a fault code. That is why I suggested monitoring the switches or live data. That would show whether or not the switch being depressed is being seen by the module.
 

narkeleptk

Active Member
The two R/Y (red wire with yellow stripe) will have battery voltage. One is probably for a lamp, one is for control just like in the rear switches where they display the inside. The N (natural aka light tan) wire is the ground supply. The data lines would prob show anywhere between 1-3V if checking with a DMM set to DCV but they are not important here.
I am a bit confused tho since you mention 3 wires and the diagram shows 10 involving the passenger switch. Is this the right schematic?

1111.jpg
 
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narkeleptk, the switch does only have 3 wires. The control module has 10.
@shortbus, fully agree. Although I understand multiplexing fairly well, it has become more equipment oriented to diagnose thes issues. VW in particular has one of the most complex systems out there and probably in the forefront of this CAN BUS era as they are directly tied to Bosch who originated this system. I got a firsthand look at a very complex 2018 GTI that was brought to me with 7 main modules not communicating. Took all of them, to bring it back to life. Learned a lot about their system. Very complex.
 

narkeleptk

Active Member
narkeleptk, the switch does only have 3 wires. The control module has 10.
@shortbus, fully agree. Although I understand multiplexing fairly well, it has become more equipment oriented to diagnose thes issues. VW in particular has one of the most complex systems out there and probably in the forefront of this CAN BUS era as they are directly tied to Bosch who originated this system. I got a firsthand look at a very complex 2018 GTI that was brought to me with 7 main modules not communicating. Took all of them, to bring it back to life. Learned a lot about their system. Very complex.
Yea I forgot my coffee this morning. I even labeled it correctly on my image haha. For some reason I got to thinking that 88 was the rear switch and 68 was switch and module.

I would imagine both the lines I have marked as red should have constant battery voltages (maybe the lamp one only comes on when the lights are on not sure on that one).
 

Diver300

Well-Known Member
Most Helpful Member
On this car, this problem is only between the passenger module and the passenger switch.

The OP said:-
the front passenger electric window isn’t working correctly.
Operating the window from the driver’s side it moves up and down, no problem so the issue is not the motor.

However, using the passenger side switch the window will go down but not back up.
So the CANbus connection between the driver and passenger door modules is fine, as it is carrying the signal to go up and down.

The power to the module is fine, as is the motor.

It is just the passenger side switch talking to the passenger side window module.

Now in this case, up and down are carried on the same wires, T4am/4 and T4am/1, using a resistor ladder, so the wiring must be OK. T4am/2 is only illumination so that is a separate issue if that doesn't work.

So either the switch pack is producing the wrong resistances, or the module is interpreting them incorrectly. Given the cost of a new switch pack, (well a cheap copy) then the best solution is to try a new switch pack. If that doesn't work, it's got to be the module.

You could be more methodical and check the resistance of the switch pack in each state, but you would have to find what the resistances are supposed to be. It might be obvious, if more than one position gave the same resistance, but it might not.

It doesn't help to look at all the other stuff that can't possibly be the cause of the original problem.
 

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